Toxic agents



Patented May l8, 1937 UNITED STATES PATENT OFFICE TOXIC AGENTS Stefan Goldschmidt. Karlsrnhc, and Karl Martin,

Bruclllal. r y! assignors to the firm Kessler Chemical Corporation, New York, N. Y.

No Drawing.

Serial No. 1933 3 Claims.

tion are: phenyl-isothiocyanate, chlorphenyl-isothiocyanate, p-oxyphenyl-isothiocyanate, mand p-phenylene-di-isothiocyanate, toluylene-di-isothiocyanate, chlorphenylene-di-isothiocyanate, nitro-phenyl-isothiocyanate, benzyl-isothiocya nate, and xylylene-di-isothiocyanate.

As compared with aliphatic isothiocyanates the aromatic isothiocyanates according to the invention are distinguished by a considerably greater toxic efle ct against fish and insects, and from a technical point oi view are also cheaper to produce. In comparison with the corresponding thiocyanatesthe isothiocyanates are much more eirective, and in particular have a more rapid efkct and do not possess a disagreeable odour and ofler greater resistance to saponiiying agents.

Thus, for example, a solution of .5 mg. p-phenylene di-isothiocyanate in 1 litre or water after standing for three days at ordinary room temperature does not reveal any decrease in the toxic effect on goldfish.

Thiocyanates also reveal unpleasant physiological efl'ects, and more particularly a biting effect, on the human skin,

to the invention. The latter do mentally on plants.

They may be employed in desired fashion, for

example by spraying on in conjunction with the also not act detriusual diluting and moistening agents in the form which is'not the case in connection with the isothiocyanates according Application December 13, 1934, 757,377. In Germany December 27,

more particularly nicotine. derris extract or retenone, in which connection there is obtained a surprising efiect greatly exceeding a mere aggregation.

The following examples will serve to explain the invention: Y

.4. Experiments with fish.

treat" 0 e 090 Substance in water or Dead altar goldfish, in

Hoim Phenylisothiocyanate v .0005 1% mand p-phenylene-di-isothiocyanate. 00001 0 i-chlor-Llihen lene-di-isothiooyanate. .00001 3 tlh liso l'll ig g I '00005 t m 0 any yana 0-.-.

.000025 14 p-oxyphenyiisothiocyanate... 00005 2% Alpha-naphthylisothiocyanate .0001 5 Benzyl-lsothiocyanate 00005 5 m-xylylene-di-isothiocyanate 00005 2% B. Experiments 00;. plants 1. A solution, containingin addition to a moistening agent .05% 'm-phenylene di-isothiocyanate in water, was sprayed on to an apple tree attacked by tree lice. The leaves did not burn.

App oximately -60% of the lice were dead after two days.

2. In a similar experiment with a .04% solution on an apple tree attacked by greenfly 50-60% were killed.

As an example of the fact that isothiocyanates retain their effectiveness also in mixture with other toxic agents'reference may be made to the following:

or m-phenylene di-isothiocyanate is increased by 3. A solution was produced in water containing,

" heating beyond 30-35 C., it acts as a breathing nate in which the isothiocyanate radical is dipoison. Gnats are killed after a few seconds, rectly attached to an aromatic nucleus.

and in the case of meal-worms this takes place 2. As an insecticide a preparation comprising after approximately 15 minutes. phenyl-isothiocyanate.

What we claim as new and desire to secure .3. As an insecticide a preparation comprising 5 by Letters Patent is: phenylene-di-isothiocyanate.

1. As an insecticide a preparation comprising STEFAN GOLDSCHMIDT.

as an active constituent an aromatic isothiocya- KARL MARTIN. 

